ryantrinh10 wrote:
We used Disk Utility instead of the BCA because whenever we used the BCA to create a partition, Windows kept giving me an error saying "Windows cannot be installed to this disk. The selected disk has an MBR partition table. On EFI systems, Windows can only be installed to GPT disks."
1. You should not interrupt BC/Windows installation and use Alt/Option key to select EFI boot. It defeats the purpose of BCA. All Macs prior to Late 2013 are preUEFI and will not properly support EFI boot.
2. Once this happens, the error message you refer to occurs, and it is correct. BCA correctly determined that your machine is preUEFI, created an MBR, but intervention caused the first problem.
What we did was use DU to create two different Mac OS Extended Journaled partitions and use the "New" function in the Win installation to make into NTFS.
This will cause future OS X upgrades to potentially cause data loss. Your disk partitioning should now have an extra MSR partition. This also implies that BCA cannot be used to remove Windows.
I keep hearing the terms "EFI" and "CSM-BIOS" thrown around pretty frequently, could you explain the basic terms for a newbie haha?
UEFI 2.x is an Intel standard which addresses the limitations of the legacy BIOS system and is supported on GPT disks. It has a backward compatibility layer called CSM-BIOS (Compatibility Support Module) BIOS. This allows legacy OS installations on more modern hardware and is slower and has limitations.
Please see https://communities.intel.com/community/itpeernetwork/vproexpert/blog/2013/08/11 /understanding-amt-uefi-bios-and-secure-boot-relationships for a brief discussion.
Macs prior to Late 2013 have used EFI 1.1. To allow legacy Windows versions to be installed on Macs, Macs use CSM-BIOS to emulate older PCs and BIOS. This layer has no user interface unlike PCs. CSM-BIOS on Macs will hide/expose hardware as necessary at the appropriate lever (firmware/hardware) so device drivers appropriately. For example an integrated GPU with onboard Audio decoding will split the graphics and audio part and expose these as separate devices. If this is broken, GPUs may get exposed, which the OS cannot handle. Intel drivers do not know what to do with an nVidia GPU and vice-a-versa. If Windows does not appropriately handle dual-GPUs, it will crash.
You need to remove the current Windows installation, clean up your disk to a single user-visible partition (ignore EFI and Recovery HD which are hidden), and then use BCA and install using BIOS. Do not interrupt Windows installer under BCA and choose EFI boot.
Does this help better explain your issue?
